In October 2010, the National Oceanic and Atmospheric Administration (NOAA) announced it would review the status of northern blue fin tuna (Thunnus thynnus) in US waters after the Center for Biological Diversity petitioned to have the fish placed on the Endangered Species List. In May 2011, NOAA announced that, based on their review, the species did not warrant listing but that the decision will be revisited in 2013. NOAA also left open the possibility of revisiting listing sooner by naming blue fin tuna a species of concern.
Blue Fin Tuna Populations Crashing Worldwide
The northern blue fin tuna has been on the IUCN Redlist as Endangered since 1996, with the western Atlantic stock considered Critically Endangered. The closely related southern blue fin tuna (Thunnus maccoyii) is also Critically Endangered. Once blue fin tuna became popular as sushi fish in the 1970s populations around the world began to decline, dropping by more than 80% over the last 4 decades.
Blue fin tuna are slow maturing; the northern species may not spawn until they are nine years old. As a highly migratory species they are heavily fished in international waters where law enforcement is difficult, making both overfishing and illegal fishing a threat.
Deepwater Horizon Oil Spill Impacts Key Spawning Area
One of the reasons for the petition to assess blue fin tuna in US waters was concern that the BP oil spill impacted one of the few spawning areas this species uses. The western stock spawns only in the Gulf of Mexico and Florida Straits in the spring. The 2010 spawning season coincided with the Deepwater Horizon spill.
NOAA will revisit their decision not to list the blue fin tuna as endangered once data from 2011 and 2012 natural resource damage assessment reports for the Gulf, which may provide further information on just how significant the effects of the oil spill were, are available. Early estimates are that the oil spill may have affected 20% of the blue fin larvae but what longer term impacts the spill will have on the species is not clear.
Relying on ICCAT for Blue Fin Tuna Management
Placement on the US endangered species list would have required the managing agency, NOAA, to designate Critical Habitat and develop a plan for recovery of the blue fin tuna. Eric Schwaab, Assistant Administrator for NOAA’s Fisheries Service stated in an online announcement that international cooperation and strong domestic fishery management would be the best way to ensure the long–term survival of the species.
The decision was also said to be based on the assumption that countries would comply with the blue fin tuna fishing quotas. But the International Commission for the Conservation of Atlantic Tunas (ICCAT), which is charged with managing the fishery, does not have a good history in safeguarding blue fin tuna. During ICCAT’s tenure, starting in 1969, blue fin tuna numbers have fallen precipitously but fishing quotas have only been marginally reduced.
The high price blue fin tuna brings on both the legal and illegal market makes it highly unlikely that the species will be truly protected internationally. Efforts to have the tuna listed on CITES (Convention on International Trade in Endangered Species) as Appendix I have also failed. An Appendix I listing would have made international trade in blue fin tuna illegal, drastically reducing the legal market. The black market, already a big factor in tuna declines, would continue to be a problem.
As a top predator species, the impact of the loss of blue fin tuna on the ocean ecosystem balance is likely be significant. But with no agency, national or international, willing to step forward and make tough decisions to protect northern blue fin tuna, it is likely the species decline will accelerate, making recovery difficult and slow, if not impossible.
Dawn M. Smith - A vet nurse, Dawn has worked in wildlife rehabilitation and conservation around the world in addition to her veterinary hospital ...
